data "template_file" "filter" {
  template = "$${filter}"

  vars {
    filter = "${data.template_file.filter.rendered_use_defaults == "true" ? format("dd_monitoring:enabled,dd_aws_alb:enabled,env:%s", var.environment) : "${data.template_file.filter.rendered_custom}"}"
  }
}

resource "datadog_monitor" "ALB_no_healthy_instances" {
  name    = "[${var.environment}] ALB no healthy instances"
  type    = "metric alert"
  message = "${var.message}"

  query = <<EOF
    min(last_1m): (
      sum:aws.applicationelb.healthy_host_count{${data.template_file.filter.rendered}} by {region,loadbalancer}
    ) <= 0
  EOF

  evaluation_delay = "${var.delay}"
  new_host_delay   = "${var.delay}"

  thresholds {
    critical = 0
  }

  notify_no_data      = true  # Will notify when no data is received
  renotify_interval   = 0
  require_full_window = false
  timeout_h           = 0
  include_tags        = true

  tags = ["env:${var.environment}", "resource:alb", "team:aws", "provider:aws"]
}

resource "datadog_monitor" "ALB_latency" {
  name    = "[${var.environment}] ALB latency > ${var.latency_threshold_critical} ms"
  type    = "metric alert"
  message = "${var.message}"

  query = <<EOF
    avg(last_5m): (
      avg:aws.applicationelb.target_response_time.average{${data.template_file.filter.rendered}} by {region,loadbalancer}
    ) > ${var.latency_threshold_critical}
  EOF

  evaluation_delay = "${var.delay}"
  new_host_delay   = "${var.delay}"

  thresholds {
    critical = "${var.latency_threshold_critical}"
    warning  = "${var.latency_threshold_warning}"
  }

  notify_no_data      = true  # Will notify when no data is received
  renotify_interval   = 0
  require_full_window = false
  timeout_h           = 0
  include_tags        = true

  tags = ["env:${var.environment}", "resource:alb", "team:aws", "provider:aws"]
}

resource "datadog_monitor" "ALB_httpcode_elb_5xx" {
  name    = "[${var.environment}] ALB HTTP code 5xx > ${var.httpcode_elb_5xx_threshold_critical} %"
  type    = "metric alert"
  message = "${var.message}"

  query = <<EOF
    sum(last_5m): (
      avg:aws.applicationelb.httpcode_elb_5xx{${data.template_file.filter.rendered}} by {region,loadbalancer}.as_count() /
      avg:aws.applicationelb.request_count{${data.template_file.filter.rendered}} by {region,loadbalancer}.as_count() * 100
    ) > ${var.httpcode_elb_5xx_threshold_critical}
  EOF

  evaluation_delay = "${var.delay}"
  new_host_delay   = "${var.delay}"

  thresholds {
    critical = "${var.httpcode_elb_5xx_threshold_critical}"
    warning  = "${var.httpcode_elb_5xx_threshold_warning}"
  }

  notify_no_data      = false # Will notify when no data is received
  renotify_interval   = 0
  require_full_window = false
  timeout_h           = 1
  include_tags        = true

  tags = ["env:${var.environment}", "resource:alb", "team:aws", "provider:aws"]
}

resource "datadog_monitor" "ALB_httpcode_elb_4xx" {
  name    = "[${var.environment}] ALB HTTP code 4xx > ${var.httpcode_elb_4xx_threshold_critical} %"
  type    = "metric alert"
  message = "${var.message}"

  query = <<EOF
    sum(last_5m): (
      avg:aws.applicationelb.httpcode_elb_4xx{${data.template_file.filter.rendered}} by {region,loadbalancer}.as_count() /
      avg:aws.applicationelb.request_count{${data.template_file.filter.rendered}} by {region,loadbalancer}.as_count() * 100
    ) > ${var.httpcode_elb_4xx_threshold_critical}
  EOF

  evaluation_delay = "${var.delay}"
  new_host_delay   = "${var.delay}"

  thresholds {
    critical = "${var.httpcode_elb_4xx_threshold_critical}"
    warning  = "${var.httpcode_elb_4xx_threshold_warning}"
  }

  notify_no_data      = false # Will notify when no data is received
  renotify_interval   = 0
  require_full_window = false
  timeout_h           = 1
  include_tags        = true

  tags = ["env:${var.environment}", "resource:alb", "team:aws", "provider:aws"]
}

resource "datadog_monitor" "ALB_httpcode_target_5xx" {
  name    = "[${var.environment}] ALB target HTTP code 5xx > ${var.httpcode_target_5xx_threshold_critical} %"
  type    = "metric alert"
  message = "${var.message}"

  query = <<EOF
    sum(last_5m): (
      avg:aws.applicationelb.httpcode_target_5xx{${data.template_file.filter.rendered}} by {region,loadbalancer}.as_count() /
      avg:aws.applicationelb.request_count{${data.template_file.filter.rendered}} by {region,loadbalancer}.as_count() * 100
    ) > ${var.httpcode_target_5xx_threshold_critical}
  EOF

  evaluation_delay = "${var.delay}"
  new_host_delay   = "${var.delay}"

  thresholds {
    critical = "${var.httpcode_target_5xx_threshold_critical}"
    warning  = "${var.httpcode_target_5xx_threshold_warning}"
  }

  notify_no_data      = false # Will notify when no data is received
  renotify_interval   = 0
  require_full_window = false
  timeout_h           = 1
  include_tags        = true

  tags = ["env:${var.environment}", "resource:alb", "team:aws", "provider:aws"]
}

resource "datadog_monitor" "ALB_httpcode_target_4xx" {
  name    = "[${var.environment}] ALB target HTTP code 4xx > ${var.httpcode_target_4xx_threshold_critical} %"
  type    = "metric alert"
  message = "${var.message}"

  query = <<EOF
    sum(last_5m): (
      avg:aws.applicationelb.httpcode_target_4xx{${data.template_file.filter.rendered}} by {region,loadbalancer}.as_count() /
      avg:aws.applicationelb.request_count{${data.template_file.filter.rendered}} by {region,loadbalancer}.as_count() * 100
    ) > ${var.httpcode_target_4xx_threshold_critical}
  EOF

  evaluation_delay = "${var.delay}"
  new_host_delay   = "${var.delay}"

  thresholds {
    critical = "${var.httpcode_target_4xx_threshold_critical}"
    warning  = "${var.httpcode_target_4xx_threshold_warning}"
  }

  notify_no_data      = false # Will notify when no data is received
  renotify_interval   = 0
  require_full_window = false
  timeout_h           = 1
  include_tags        = true

  tags = ["env:${var.environment}", "resource:alb", "team:aws", "provider:aws"]
}